Childhood obesity is a rising problem in India; estimates expect as many as 17 million kids will be obese by 2025, if nothing changes. Which is why we need all of the information around the condition we can get. Luckily, a new study suggests the causes of childhood obesity lie less in specific parenting choices around feeding, and more in whether parents are responding to their children’s stress in a way that matches children’s genetic emotional disposition.

Earlier studies have pinned the causes of childhood obesity mainly on parents’ restrictive feeding practices and negative communication around food, which can interfere with a child’s ability to learn to self-regulate food intake. And it’s true — but mainly for children who carry a specific set of amino acids in a protein produced by their COMT gene. The COMT gene is known for its significant impact on emotion and cognition; that protein it produces helps regulate the levels of dopamine in the brain. And that protein could either carry valine (VAL) amino acids or methionine (MET), a microscopic difference arbitrarily determined by what an individual has inherited from each parent.

In a child with VAL, “the COMT system works three to four times faster than those with other combinations do, and therefore accumulates less dopamine in the front of the brain,” Bost said. “Children who have at least one copy of VAL tend to be more resilient emotionally. Those who are MET carriers have the propensity to be more reactive to negative emotion or stress.”

By pairing the genetic information of 126 children with their parents’ responses to a questionnaire around how they respond when their children get upset, Bost and colleagues discovered that the genetic part of children’s dispositions can rub up against parenting tactics in a way that makes them more likely to become obese. The same parents who were most likely to use restrictive feeding also reported more frequent punishment or dismissal of their children’s response to stress; these parents also tended to be the parents of MET carriers with higher weight. The same was not necessarily true for children who were VAL carriers.

While traditional interventions for preventing childhood obesity teach parents to provide good nutrition or how to make meals less stressful, Bost is calling for newer interventions that help parents suit their tactics to their children’s genetic emotional disposition.

“Sometimes the way parents respond is based on their own stress, belief systems, or the way they were raised,” she said. “Educating parents from a developmental perspective can help them to respond to their children’s emotions in ways that will help their children learn to self-regulate their emotions and their food intake.

“Children respond to us in different ways based on their own temperament, genotype, and history of interactions. Responsive parenting involves an understanding of what stress-reducing approaches are most effective for a particular child.”

The study was co-authored by Margarita Teran-Garcia, Sharon Donovan, and Barbara Fiese, all of the University of Illinois, and published in Pediatric Obesity.